共查询到17条相似文献,搜索用时 78 毫秒
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Al_2O_3Cu-Ti-Zr/Nb钎焊研究 总被引:3,自引:0,他引:3
使用Cu Ti Zr钎料对Al2 O3 Nb进行了钎焊试验。通过扫描电镜、能谱、X射线衍射分析了界面形貌、元素分布 ,并对反应相进行了判定。Cu70 Ti2 5 Zr5 钎料在 12 93K、10min条件下界面产生了 3种新相 :Cu2 Ti4O、Ti固溶体、CuTi,界面结构为Al2 O3 Cu2 Ti4O Ti固溶体 CuTi Cu固溶体 +CuTi。采用拉剪试验评定了强度 ,结果证实12 93K、10min ,使用Cu70 Ti2 5 Zr5 钎料的接头强度最高达到 16 2MPa ,增加或减少Ti的质量分数以及改变保温时间都会使接头抗剪强度下降。 相似文献
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Al2O3/(Ag72Cu28)97Ti3/Ti-6Al-4V界面反应 总被引:1,自引:0,他引:1
《机械工程学报》2002,38(2):31-34
在1.8 ks、1
073~1 173 K条件下对Al2O3/(Ag72Cu28)97Ti3/Ti-6Al-4V进行了钎焊试验.通过扫描电镜、波谱、能谱和X射线衍射对界面反应产物进行了测试,确定了界面结构,并讨论了这些反应产物形成的可能性.结果表明,温度小于1
123 K的界面结构为Al2O3/Cu2Ti4O/Cu4Ti3+Cu固溶体/Ag-Cu共晶 + 富Ag相;温度1 173
K的界面结构为Al2O3/Cu3TiO5 + CuAl2O4/Cu4Ti3/富Ag相+ Cu4Ti3. 相似文献
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采用在Al2O3基体中加入NCP成孔剂的方法制备Al2O3基高强度透气性陶瓷材料,并对其性能进行了研究.结果表明加入适量NCP成孔剂,可以制得透气性好且强度高的透气性材料,可以用于一些透气性模具的制造.所研制材料的透气度及强度与预烧温度、烧结温度及酸处理条件等密切相关,材料强度高的原因主要是由于材料中气孔形状比较理想,且分布细小均匀,n值较低.当预烧温度1
42L/(m·Mpa·s),抗弯强度为251.0MPa.400℃,烧结温度1 480℃,酸处理时间为40h时,材料的综合性能较佳,透气度为0.042L/(m·Mpa·s),抗弯强度为251.0MPa. 相似文献
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采用真空热压烧结方式制备了Al2O3/ZrO2梯度复合陶瓷刀具材料,并对ZrO2含量及梯度结构层厚比进行了优化。层厚比为2.0的AZE20梯度复合陶瓷刀具材料维氏硬度为(18.7±0.33) GPa,抗弯强度为(937±28.5) MPa,断裂韧性为(8.2±0.32) MPa·m1/2,相比最佳ZrO2含量的均质复合陶瓷刀具材料AZ20,维氏硬度、抗弯强度和断裂韧性分别增加了22%、37.8%和43.8%。梯度结构的设计使表层形成残余压应力,晶粒得到一定程度的细化,更多的ZrO2晶粒因残余压应力尺寸稳定在t相ZrO2晶粒尺寸。在复合材料断口形貌中发现,其断裂方式为表层穿晶断裂和中间层沿晶断裂的结合,这种混合断裂方式使刀具整体力学性能得到提高。 相似文献
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以Al2O3-13%TiO2(AT13)和纳米掺锑SnO2(Sb-SnO2)粉体为原料,采用等离子喷涂工艺在4145H合金钢基体表面制备了掺杂不同质量分数(0~16%)Sb-SnO2的AT13复合陶瓷涂层,研究了复合陶瓷涂层的表面性能、微观形貌、显微硬度、结合强度以及在地层采出水中的抗结垢性能,并与电镀铬层和未处理4145H合金钢进行对比。结果表明:与电镀铬层和未处理4145H合金钢相比,复合陶瓷涂层的水接触角较大,表面能较低,随着Sb-SnO2掺杂量的增加,水接触角基本呈先增大后减小的趋势,表面能先减小后增大;复合陶瓷涂层具有大量的孔隙;随着Sb-SnO2掺杂量的增加,硬度整体呈降低趋势,但均高于4145H合金钢和电镀铬层,单位面积结垢质量先减小后增大;掺杂质量分数10%Sb-SnO2的复合陶瓷涂层具有最大的水接触角、最小的表面能、最小的单位面积结垢质量,平均结合强度为25.7 MPa。 相似文献
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采用GPS+HIP生产工艺制造Al2O3基陶瓷刀片 总被引:2,自引:0,他引:2
《工具技术》2001,35(6):27-29
介绍了采用GPS+HIP生产工艺制造Al2O3基陶瓷刀片所涉及的混料、压制、排胶、气氛保护烧结(GPS)、热等静压(HIP)处理、刀片刃磨等主要生产工序。 相似文献
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Influence of Al2O3 reinforcement on the abrasive wear characteristic of Al2O3/PA1010 composite coatings 总被引:2,自引:0,他引:2
In the present study, the abrasive wear characteristics of Al2O3/PA1010 composite coatings were tested on the turnplate abrasive wear testing machine. Steel 45 (quenched and low-temperature tempered) was used as a reference material. The experimental results showed that when the Al2O3 particles have been treated with a silane coupling agent (γ-aminopropyl-triethoxysilane), the abrasive wear resistance of Al2O3/PA1010 composite coatings has a good linear relationship with the volume fraction of Al2O3 particles in Al2O3/PA1010 composite coatings and the linear correlation coefficient is 0.979. Under the experimental conditions, the size of Al2O3 particles (40.5-161.0 μm) has little influence on the abrasive wear resistance of Al2O3/PA1010 composite coatings. By treating the surface of Al2O3 particles with the silane coupling agent, the distribution of Al2O3 particles in PA1010 matrix is more homogeneous and the bonding state between Al2O3 particles and PA1010 matrix is better. Therefore, the Al2O3 particles make the Al2O3/PA1010 composite coatings have better abrasive wear resistance than PA1010 coating. The wear resistance of Al2O3/PA1010 composite coatings is about 45% compared with that of steel 45. 相似文献
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Very little research effort has been directed at development of models of erosion–corrosion of composite materials. This is because, in part, the understanding of the erosion–corrosion mechanisms of such materials is poor. In addition, although there has been a significant degree of effort in the development of models for erosion of MMCs, there are still difficulties in applying such models to the laboratory trends on erosion rate.In this paper, the methodology for mapping erosion–corrosion processes in aqueous slurries was extended to particulate composites. An inverse rule of mixtures was used for the construction of the erosion model for the particulate MMCs. The corrosion rate calculation was evaluated with reference to the matrix material.The erosion–corrosion maps for composites showed significant dependency on pH and applied potential. In addition, the corrosion resistance of the matrix material was observed to affect the regime boundaries. Materials maps were generated based on the results to show the optimum composite composition for exposure to the environment. 相似文献
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Sliding wear characteristics of plasma-sprayed Al2O3 and Cr2O3 coatings against copper alloy under severe conditions 总被引:2,自引:0,他引:2
Al2O3 and Cr2O3 coatings were deposited by atmospheric plasma spraying and their tribological properties dry sliding against copper alloy were evaluated using a block-on-ring configuration at room temperature. It was found that the wear resistance of Al2O3 coating was superior to that of the Cr2O3 coating under the conditions used in the present study. This mainly attributed to its better thermal conductivity of Al2O3 coating, which was considered to effectively facilitate the dissipation of tribological heat and alleviate the reduction of hardness due to the accumulated tribological heat. As for the Al2O3 coating, the wear mechanism was plastic deformation along with some micro-abrasion and fatigue-induced brittle fracture, while the failure of Cr2O3 coating was predominantly the crack propagation-induced detachment of transferred films and splats spallation. 相似文献
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Reciprocating sliding friction experiments were conducted with various two-phase, directionally solidified Al2O3/ZrO2 (Y2O3) pins sliding on B4C flats in air at temperatures of 296, 873, and 1073 K under dry sliding conditions. Results indicate that all the Al2O3/ZrO2 (Y2O3) ceramics, from highly Al2O3-rich to ZrO2-rich, exceed the main wear criterion requirement of 10−6 mm3 N−1 m−1 or lower for effective wear-resistant applications. Particularly, the eutectics and Al2O3-rich ceramics showed superior wear properties. The composition and microstructure of Al2O3/ZrO2 (Y2O3) ceramics played a dominant role in controlling the wear and friction properties. The controlling mechanism of the ceramic wear, friction, and hardness was an intrinsic effect involving the resistance to shear fracture of heterophase bonding and cohesive bonding and the interlocking microstructures at different scales in the ceramics. 相似文献
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Austenitic stainless steels are used in applications demanding general corrosion resistance at room or moderate operating temperatures. However, their use is often limited by the relative softness of these materials and their suceptibility to wear and galling. The present investigation deals with the dry sliding wear behaviour of two P/M austenitic stainless steels (AISI 304L and 316L) and their composites containing two different ceramic particles (Al2O3 and Y2O3) and two different sintering activators (BN and B2Cr). Unlubricated pin-on-disc wear tests were carried out. Wear mechanisms were analysed by means of scanning electron microscopy and X-ray diffraction. A plastic deformation and particle detachment wear mechanism was revealed. Plasticity during sliding induced an austenite to martensite transformation. The presence of ceramic particles (Al2O3 and Y2O3) and sintering activators (B2Cr, BN) improved significantly the wear resistance (especially the combination Al2O3 and B2Cr). Ceramic particles limited plastic deformation while sintering activators decreased final porosity. 相似文献